Ceramic material.



' UNITED sTA T Es IiATENT OFFICE.

ANDREW MALINOVSZKY, OF CHICAGO, ILLINOIS, ASSIGNOR TO HARRY H. RANDOLPH,

OF CHICAGO, ILLINOIS.

CERAMIC MATERIAL.

No Drawing.

Specification of Letters Patent.

Application filed March 13, 1912.

Patented Sept. 15, 1914.. Serial No. 683,533.

T 0 all whom it may concern:

Belt known that I, ANDREW MALINOV- $2111, a citizen of theUnited-States, res1d-' ing at Chicago, in the county of Cook and to themanufacture of bricks, tiles and othersimilar articles.-

It is the object of my invention to produce bricks which will have afine texture, possess a high tensile strength, absorb moisture only to avery small degree, and resist the action of frost.

. The principal ingredients which enter into the manufacture of theproducts made according to my invention are silica, the oxid or othersuitable salt of an earth metal or metals, and alkali, together withvarious impurities, such, for example, as iron. I use the term earthmetal in a broad sense. and refer not only to the metals such asaluminum, to which this term is commonly applied, but also to thealkaline earth metals,

such as calcium, magnesium, strontium, ba-

rium, and the like. I prefer, however, to use aluminum as the earthmetal, since this element produces ceramic material. of a better textureand finish than that produced by the other earth metalsqvhich I havementioned. Under the term alkali I include the oxids or other suitablesalts of metals, such as sodium, potassium and lithium.

The materials from which the bricks or other articles are made arepreferably granite, clay, and sand, but it will be understood that othermaterials, such as feldspar, slag, or the like, may be used withoutdeparting from the spirit of my invention. The essential point is thatthe aggregate chemical composition of the materials used to produce thefinished brick should be substantially wfithin the limits which will begiven herea ter.

In carrying out my invention I first crush a reducing flame is used toheat the granite,

while if a brick of dark color is desired an oxidizing flame is used. Inthe former case the oxid of iron contained in the granite is reduced tothe form of ferrous oxid (FeO), while in. the latter the oxid isoxidized to ferric oxid (Fe O The granite is next finely pulverized andmixed with the finely pulverizedclay and sand. A portion of this sand.is ground to be of sufiicient fineness to pass through a 100-meshscreen, whereas the balance is coarser so that it will pass through a 40to'60-mesh screen. terial is now mixed with water, molded, and placed ina kiln, where it is burned according to the usual well-known system.

The preferred composition of the finished material which I obtain is asfollows: Silica(SiO,)-65-85% (preferably 76%) alumina (A1 0 1020%(preferably 15%); oxid of iron(FeO or Fe,O,) trace to 3% (preferably1%); sodium or potassium oxid(Na,O or'K,O)2.5-4% (preferably 3%).

It will be understood by those skilled in the art that the compoundsgiven in the above table unite with each other to form silicates ofcomplex composition, but, accordlng to the usual system used inreporting chemical analyses, I have designated,

the various elements both in this table and in the claims which formpart of this speciabove-mentioned composition is as follows:

Granite. Clay. Sand.

00 30. 00 97. 00 00 43. 00 2. 00 00 2. 00 Tr. Tr. Ti. 0.00 Tr. 60 0. 0029 1. 60 T1. 73 0. 00 0. 00 Q0 13. 00 0. 00

When materials of the above analyses are used, I employ about 30% ofgranite, 20% of clay, and 50% of sand in order to obtain the finishedmaterial of desired analysis. As previously mentioned, a portion of thesand which I mix with the granite and clay is very finely pulverized,whereas the balance The ma-' is much coarser. The fine sand is used inthe eutectic ratio, that is suflicient quantity so that'it is justenough, with the silica contained in the granite and clay, to form thesilicates of the bases which I use, according to the followingreactions:

On the assumption that 15% of alumina, 1% of oxid of iron, and 3% ofpotassium oajid are used, it will be found by the proper computation ofcomparative molecular Weights that 26% of silica is necessary to formthe aluminium silicate, A1 (SiO,) 1% to form the ferric silicate,Fe,(SiO and 2% to form the potassium silicate, K SiO or a total of 29%,in order to be just suflicient to combine with all of the bases to formthe corresponding silicates. This amount of silica I add in a finelypulverized condition, whereas the balance of coarse sand is for thepurposefof forming a skeleton-like structure throughout the brick, tile,or other similar object.

In the manufacture of my improved product the potassium or otheralkaline silicate is first formed at a comparatively low temperature.This fused silicate in turn acts as a catalytic agent, and assists inthe forma-' tion of the silicates of the earth metals, such as aluminum,calcium, and the like, and also in the formation of the silicates of theother elements, such as iron, which may be present as impurities.- Thesilicates of the earth .metals and of the impurities, such as iron, arethereby formedat a lower temperature than that at which such silicateswould be formed without the presence of a catalytic agent; The fusintemperatures of the silicates thus formedare considerably lower than thefusing point of pure silica, so that .the desired reactionstake placebefore the coarse sand is affected. By-using the proportions I havementioned there is a considerable difference, at least -150- 0., betweenthe temperature of vitrification, which is the temperature at which thesilicates are formed, andth-"e temperature of viscosity, which is thetemperature at which the sand'itself begins melt. Thi'sjis a point ofgreat 'prac tical importance, s nce in this wayit is un-;

necessary watch the temperatures in the 111111 nearly as closely vasi'sthe .case 'in .crdi-, y practica. .4

- V'ihen the above-mentioned formula is employed-for-the-manufacture oftiles or other similar objects which are comparatively thin, I havefound it of great advantage to add a certain percentage of starch orother similar binding material to the water which is mixed with thepulverized materials before they are subjected to the final action ofthe kiln. Under ordinary circumstances 2% of starch mixed with the wateris amply sufiicient, and by its lise the tiles may readily be handledwithout danger of breaking.

By using the formula mentioned above, I have found that in molding thebricks the process ordinarily known as the stiff-mud process may beemployed, WhlCh consists in forcing the material through a die andsubsequently cutting into desired lengths by Wire. On account of thecheapness of this process it is a great advantage to be able to employthe same.

It Will be apparent to those skilled in the art that many changes couldbe made in the details of my invention Without departing from the spiritor scope thereof.

What I claim is:

1. As a new article of manufacture, ceramic material made fromsubstances containing oxid of earth metal; oxid of alkali metal; finelydivided silica in the eutectic ration to form the silicates of saidearth metal and said alkali metal; and a relatively coarse materialadapted to form the framework of the ceramic product and infusible atthe temperature of formation of said sili-. cates; substantially asdescribed.

2. As a new article of manufacture, ceramic material made fromsubstances containing alumina, oxid of alkali metal, finely dividedsilica in the eutectic ratio to form I the silicates of the aluminum andsaid alkali eutectic ratio to form the silicates of the aluminum andsaid alkali metal, and relatively coarse silica adapted to form theframework of the ceramic product, substantially as described.

ANDREW MALINOVS'ZKY.

Witnesses: HENRY M. HUXLEY, H. H. RANDOLPH.

